ComJam,
Has your internet explorer got stuck in offline mode?
To check this go to the file menu and second from bottom option should be work online.
Another thing to check i whether you can navigate to your routers built in web page - usually
http://192.168.1.1 or
http://192.168.2.1 - if it can then it sounds like it could be a DNS issue - come back and let us know.
Cheers